000
AXNT20 KNHC 181739
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SUN JAN 18 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 7N10W CROSSES THE EQUATOR NEAR 
20W THEN ALONG 1S30W 1S40W TO NE BRAZIL NEAR 2S44W. WIDELY 
SCATTERED MODERATE CONVECTION IS FROM 3S-1N BETWEEN 24W-34W. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM EQ-4N 
BETWEEN 34W-41W. SCATTERED MODERATE CONVECTION IS ALONG THE 
COAST OF BRAZIL FROM 4S-EQ BETWEEN 40W-46W. 

...DISCUSSION...

GULF OF MEXICO...
THE TAIL END OF A COLD FRONT HAS ENTERED THE NW GULF OF MEXICO 
OFF THE COAST OF TEXAS. RADAR IMAGERY SHOWS PREFRONTAL SHOWERS 
EXTEND FROM THE FLORIDA PANHANDLE TO S OF LOUISIANA ALONG 31N85W 
29N91W. 10-15 KT NW FLOW IS N OF THE FRONT. MOSTLY 5-10 KT SW 
FLOW IS S OF THE FRONT. A WEAK 1024 MB HIGH IS CENTERED OVER 
CENTRAL FLORIDA NEAR 28N82W. TEMPERATURES ARE IN THE 60'S AND 
70'S S OF THE FRONT. IN THE UPPER LEVELS...THE BASE OF AN UPPER 
LEVEL TROUGH IS OVER THE GULF WITH AXIS ALONG 85W. UPPER LEVEL 
MOISTURE IS OVER THE W GULF W OF 90W BETWEEN 22N-28N. THE 
REMAINDER OF THE GULF HAS STRONG SUBSIDENCE ALOFT. A 110-130 KT 
JETSTREAM IS OVER THE CENTRAL GULF ALONG 25N. EXPECT...THE COLD 
FRONT TO EXTEND FROM THE STRAITS OF FLORIDA TO THE BAY OF 
CAMPECHE IN 24 HOURS WITH SHOWERS. 
 
CARIBBEAN SEA...
A SURFACE TROUGH EXTENDS FROM HISPANIOLA TO N OF PANAMA. 
SCATTERED SHOWERS ARE ALONG THE TROUGH. CLUSTERS OF BROKEN LOW 
CLOUDS AND SCATTERED SHOWERS ARE ALSO ALONG THE COAST OF COSTA 
RICA..AND ALONG THE COAST OF N HONDURAS. MODERATE TO FRESH 
TRADEWINDS OVER THE CARIBBEAN SEA AND CENTRAL AMERICA. IN THE 
UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE W CARIBBEAN W 
OF 70W. AN UPPER LEVEL RIDGE IS OVER THE E CARIBBEAN WITH AXIS 
ALONG 63W. STRONG SUBSIDENCE IS OVER THE ENTIRE CARIBBEAN AND 
CENTRAL AMERICA. EXPECT...THE SURFACE TROUGH TO MOVE W OVER THE 
NEXT 24 HOURS WITH SHOWERS.

ATLANTIC OCEAN...
A STATIONARY FRONT IS OVER THE W ATLANTIC FROM 32N55W TO 29N62W 
N OF HISPANIOLA NEAR 20N69W. BROKEN TO OVERCAST LOW CLOUDS AND 
SCATTERED SHOWERS ARE WITHIN 60 NM OF THE FRONT. A 1037 MB HIGH 
IS OVER THE E ATLANTIC NEAR 31N29W. MOSTLY BROKEN LOW 
CLOUDS ARE N OF 10N BETWEEN W AFRICA AND 45W. IN THE UPPER 
LEVELS...AN UPPER LEVEL TROUGH IS OVER THE W ATLANTIC W OF 70W. 
A RIDGE IS BETWEEN 60W-70W. AN UPPER LEVEL LOW IS E OF THE 
LESSER ANTILLES NEAR 17N48W. A LARGE UPPER LEVEL HIGH IS 
CENTERED OVER THE E ATLANTIC NEAR 27N32W.    

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FORMOSA